A storage system is designed such that a plurality of drives (for example, Hard Disk Drives (HDDs)) have a Redundant Arrays of Inexpensive Disks (RAID) configuration or a path between a storage controller and a drive is multiplexed in order to enhance fault tolerance. PTL 1 discloses a storage subsystem in which when a fault site is detected in a connection path for a drive unit, the connection path is reconstructed so as to bypass or avoid the fault site.